1. Field of the Invention
The present invention relates to an image processing apparatus and particularly to an image processing apparatus displaying a key for setting its own function.
2. Description of the Related Art
In recent years, such image processing apparatuses as a digital copying machine and an MFP (Multi-Functional Peripheral) have more functions and a large number of functions are provided in one apparatus. Meanwhile, a display space on an operation panel included in the MFP is limited and hence it is difficult to simultaneously display keys corresponding to all functions (setting) provided in the MFP on the operation panel. If simultaneous display of all function keys on the operation panel is attempted, keys become smaller in size and an interval between the keys inevitably becomes narrow. Consequently, an erroneous operation is more likely and operability becomes poor.
In order to address this, document 1 (Japanese Laid-Open Patent Publication No. 2004-306478) discloses a technique for displaying a plurality of windows in an image forming apparatus. In the image forming apparatus, when a function key in a function setting screen (a function setting main screen) is selected, a function setting sub screen corresponding to the selected function key is displayed in a manner superimposed on a part of the function setting main screen.
In addition, document 2 (Japanese Laid-Open Patent Publication No. 2006-085683) discloses a technique substantially the same as in document 1 that a plurality of windows are displayed in a computer system having a graphical user interface.
According to these techniques, a new setting screen (a sub window) is displayed in response to a user's operation, in a manner superimposed on an original setting window (a main window), and hence more complicated setting can be made in a limited display space.
According to the techniques described in document 1 and document 2, however, for example, when the user selects a key in connection with a “function 1” in the main window, a sub window for making detailed setting in connection with “function 1” is displayed in a manner superimposed on the main window. In such a situation, the user can make detailed setting for “function 1”, whereas the user cannot see a key displayed in a region in the main window under the sub window (that is, on which the sub window is superimposed). In addition, the user cannot operate a key displayed in that region either.
In general, in many cases, functions (keys) more frequently used by the user (that is, relatively of higher importance) than keys displayed in the sub window are displayed in the main window.
Therefore, according to the conventional techniques as in document 1 and document 2 that a sub window is displayed in response to a user's operation in the main window in a manner superimposed on the main window, once the sub window is displayed, the user can no longer see or operate a function of relatively high importance displayed under the sub window. In this regard, the conventional techniques have not been satisfactory in operability.